1. Field of the Invention
The invention relates to an improved piezoelectric actuator, for example for actuating a mechanical component such as a valve or the like.
2. Description of the Prior Art
It is generally known that the so-called piezoelectric effect can be used to produce a piezoelectric element comprised of a material with a suitable crystalline structure. When an external electrical voltage is applied, a mechanical reaction of the piezoelectric element occurs, which produces a pressure or tension in a direction that can be predetermined as a function of the crystalline structure and the regions to which the electrical voltage is applied. The structure of this piezoelectric actuator can be laid out in a number of layers, (multilayered piezoelectric actuators) in which the layers are respectively interspersed with the electrodes used to apply the electrical voltage. Such piezoelectric actuators can, for example, be used to operate on/off valves in fuel injection systems of motor vehicles.
A piezoelectric actuator of this kind is known from DE 100 26 005 A1, in which the outer electrodes are respectively distributed in a net-like or mesh-like fashion over a side surface and are contacted by the respective inner electrodes at least at points. The net-like or mesh-like outer electrodes extend beyond the multilayered structure of piezoelectric layers in such a way that the extensions serve to supply the electrical voltage via appropriate connections.